A PROSPECTIVE 15-YEAR FOLLOW-UP-STUDY OF MANDIBULAR FIXED PROSTHESES SUPPORTED BY OSSEOINTEGRATED IMPLANTS - CLINICAL-RESULTS AND MARGINAL BONE LOSS

In this prospective study 47 edentulous patients were treated with man dibular fixed prostheses supported by osseointegrated Branemark implan ts and followed for 12 to 15 years. Three (1%) of the 273 inserted imp lants were lost, two before and one six years after placement of the f ixed prosthesis. The cumulative success rate (CSR) of the implants was 98.9% both after 10 and 15 years. None of the fixed prostheses was lo st and at the last follow-up, all patients had stable fixed prostheses in function (CSR 100%). The marginal bone loss around the implants wa s small, on average 0.5 mm during the first post surgical year and the reafter about 0.05 mm annually More bone was lost around the anterior implants than around the most posterior ones, Smoking and poor oral hy giene had significant influence on bone loss, while occlusal loading f actors such as maximal bite force, tooth clenching and length of canti levers were of minor importance. It is concluded that the long-term re sults of the mandibular implant treatment were extremely successful, r egarding both the fixed prostheses and implant stability. Bone resorpt ion around the implants, albeit limited, was influenced by several fac tors, smoking and oral hygiene appeared to be most important.